Method and blank for making film spools



July 24, 1934. T. e. BAXENDEN ET AL 1,967,920

METHOD AND BLANK FOR MAKING FILM SPOOLS Filed July 3, 1935 j Hal Q 3 I 2 11/217 fora 3 [D ,7 3 72 17716 Gcwye flazenden Patented July 24, 1934 PATENT OFFICE METHOD AND BLANK FOR MAKING FILM SPOOLS Thomas George Baxenden, Watford, and John Robert Collyear, Bushey, England Application July 3, 1933, Serial No. 678,970 In Great Britain July 7, 1932 3 Claims.

This invention relates to photographic film spools such as are used in roll film cameras, and the construction of spool according to the invention is particularly applicable to the spools used in the smaller sizes of roll film cameras.

The object of the invention is to eliminate the milling or saw-cutting operations necessary in the usual construction of film spool to form the key slot for the winding key of the camera, or the film slot which receives the end of the film or the paper covering the film, these operations being costly from a manufacturing point of View.

According to the present invention therefore, a photographic film spool constructed wholly of metal and consisting of a cylindrical body portion and end discs secured thereon, has the cylindrical body or spindle formed from two half cylinders, that is, formed from two halves which are joined together along a plane passing through the longitudinal axis of the body and through the longitudinal film slot and the key slot therein. The body portion or spindle may be made either Ihollow or solid and is preferably formed from a strip of metal having, or formed to, a half-round shape in cross-section and of twice the length of the completed spindle, which is folded or doubled up at the centre of its length so that the two halves abut together along a plane passing through the longitudinal axis of the body and the film slot and the keyslot therein. In the case of a spool having a hollow body, the latter is formed from a metal strip which is blanked out or pressed up so as to have a half round or shallow U-form in cross-section with the necessary depressions in its longitudinal edges to form the film and key slots when the spindle is completed, while, in the case of a spool having a solid body, the body is formed from a length of half round wire or rod which is compressed at the appropriate places in its fiat face to form the depressions which ultimately form the film and key slots respectively. In each case the length of metal thus formed is doubled up to form the completed spindle as above described, and end discs are secured on the ends of the spindle to form the completed spool.

A construction according to the invention is illustrated in the accompanying drawing wherein Fig. 1 is an elevation of the strip of metal, Fig. 2 is an end view thereof, when a hollow body is to be formed, while Fig. 3 is an end View in the case of a solid body, Fig. 4 shows the completed spindle after the strip has been doubled up, while Fig. 5 shows an elevation of a complete spool.

Referring first to Figs. 1 and 2 which show the formation of a spindle of tubular or hollow form, the body is formed by taking a fiat metal strip of a length twice that of the finished spool body, and of a width equal to half the circumference of the finished body, and the strip is blankedout or formed up as shown at 1, so that it has a half round form or shallow U-form in transverse crosssection as shown in Fig. 2, while its longitudinal edges have two out out or compressed portions 2, each cut out or compressed portion being of the length of the finished film slot, and of a depth equal to half the width of the film slot, while at each end of its edges it is formed with a short cut out or compressed portion 3 which ultimately forms the key slot. The strip 1 formed in this {10 manner is then folded or doubled up at the centre of its length until the two outer ends come together as shown in Fig. 4, the edges of each half contacting down the length of the spindle in a plane passing through the film slot 4 and the .75 key slot 5, the cut out or compressed portions 2 and 3 of the edges of the blank forming such film and key slots when the strip 1 is doubled up. The cylindrical body formed in this manner may have the edges welded together or the two halves may '80 be held together by the end discs 6 which are fitted over the ends of the body as shown in Fig.

5, which illustrates a completed spool.

When the spool is to have a solid body or spindle the spindle is formed from a length of half-round wire or rod 1 shaped similarly to that shown in Fig. 1, but having an end view as shown in Fig. 3. This length of wire or rod is compressed at the appropriate places in its flat face to form the longitudinal halves 2 of the film '90 slot 4 and at the ends of its fiat face to form the two halves 3 of the key slot 5 and the length of wire after being shaped in this manner is doubled up at the centre of its length until its fiat faces contact and it has the form shown in Fig. 4, the two halves being welded together or held together by the end discs pressed over the ends of the body.

Preferably, in both the above described constructions, the method of attaching the end discs will be that described in our co-pending application, Serial No. 558,621, filed Aug. 21, 1931, or by embossing the flanges in the well known manner.

These constructions of film spool according to the invention, are cheaper and easier to construct than the usual constructions of film spools, and are light in weight and strong and rigid in use.

What we claim as our invention and desire to secure by Letters Patent is:

l. The improved method of making a photographic film spool having a film slot and a key slot which consists in shaping a piece of metal into a half round shaped strip having a length substantially twice that of the finished spool body and a Width substantially half that of the finished spool, forming spaced elongated recesses in said. strip at points equally spaced from the ends thereof, each of said recesses having a length substantially equal to that of the finished film slot and a depth equal to half the width of the finished film slot compressing the end portions of said strip, and folding the strip upon itself at its 1on gitudinal center until the longitudinal edges of the two halves of the folded strip abut and the recesses and depressed portions respectively register to form the film slot and key slot respec-- tively, and Welding the abutting edges together. 2. The improved method of making a. photographic film spool having a film slot and a key slot which consists in shaping a piece of metal into a halfround shaped strip having a length substantially twice that of the finished spool body and a width substantially half that of the finished spool, depressing the edges of said strip for a distance equal to the length of the film slot at points equi-distant from the longitudinal center thereof to provide raised portions between said depressed portions and outwardly thereof, cutting away a portion of the edges of said strip at each end thereof, and doubling up the strip at the longitudinal center thereof until the raised portions abut and the depressed portions and cut away portions respectively register, x

3. A blank for making spindles of photographic film spools having a film slot and a key slot comprising an integral strip of metal half round in cross-section and having a length substantially twice that of the finished spindle and a width substantially half that of the finished spindle, said strip being provided in each half thereof with a depressed portion having a length substantially equal to that of the finished film slot and a depth equal to substantially half the width of the finished film slot, said strip also being provided at each end with a cut away portion, said strip adapted to be folded at its longitudinal center to bring the edges of each half thereof into abutting relation and to bring the depressed portions and. cut away portions respectively into registry.

THOMAS GEORGE BAXENDEN. JOHN ROBERT COLLYEAR. 

